"'Watchmen' changed everything." This isn't exactly a revolutionary statement: people have been opining about the significance of Alan Moore and Dave Gibbons's dystopic superhero graphic novel for 30 years. But the story of Rorschach, Dr. Manhattan and Ozymandias didn't just help launch the "grim-'n-gritty" take on the superhero genre we're still experiencing today. It also helped change many folks' expectations of what pop-culture could reflect back to us. Oliver Sava is a brilliant comics critic who writes for the A/V Club and other places, and he helps us sort through the amazing depth and breadth of "Watchmen."